Driving circuit and driving controller capable of adjusting internal impedance

ABSTRACT

A driving circuit includes a power supply, a plurality of conductive paths and a plurality of driving controller. The power supply is configured for providing a predetermined voltage. The conductive paths are connected to the power supply to receive the predetermined voltage. The driving controllers are connected to the conductive paths correspondingly. A first driving controller of the driving controllers has a first internal circuit configured for employing an internal voltage to perform functions provided by the first driving controller, and a resistance adjustment unit. The resistance adjustment unit is connected between a special conductive path and the first internal circuit. The second driving controller has a second internal circuit configured for employing a second internal voltage to perform functions provided by the second driving controller. A resistance value of the resistance adjustment unit is adjustable to make the first internal voltage same to the second internal voltage.

CROSS-REFERENCE TO RELATED APPLICATIONS

This is a continuation application of an application Ser. No.12/356,517, filed Jan. 20, 2009 which is based upon and claims thebenefit of priority from the prior Taiwanese Patent Application No.097117203, filed May 9, 2008, the entire contents of which areincorporated herein by reference.

FIELD OF THE INVENTION

The present invention relates to a driving circuit, and moreparticularly, to a driving circuit adapted to a liquid crystal displaypanel and a driving controller capable of adjusting internal impedancethereof.

BACKGROUND OF THE INVENTION

Generally, a typical thin film transistor liquid crystal display(TFT-LCD) includes an upper panel having a color filter, a lower paneland liquid crystal filled between the upper panel and the lower panel. Aplurality of scanning lines (gate lines) and a plurality of data lines(source lines) crossed above the plurality of scanning lines, are formedon the lower panel. A plurality of thin film transistors (TFT) arrangedin an array, are adjacent to intersections defined by the scanning linesand the data lines respectively. Each TFT is configured for determiningwhether or not transmit a data signal of the corresponding data lineelectrically connected to this TFT, to a corresponding pixel, accordingto a controlling signal of the corresponding scanning line electricallyconnected to this TFT. Therefore, each TFT is used as a switch for thecorresponding pixel.

FIG. 1 is a circuit block diagram of a typical liquid crystal display(LCD) panel. As shown in FIG. 1, a TFT-LCD panel 10 includes a board 12,a printed circuit board 14 and a plurality of flexible printed circuitboards 16. The flexible printed circuit boards 16 are electricallycoupled between the printed circuit board 14 and the board 12. Theprinted circuit board 14 includes essential electronic members, such asa power supply (not shown) and a time controller (not shown), etc.,formed thereon. A plurality of scanning lines GL1, GL2, . . . GLm, and aplurality of data lines DL1, DL2, . . . DLn, are formed on the board 12.The plurality of scanning lines GL1, GL2, . . . GLm, are crossed aboveor below the plurality of data lines DL1, DL2, . . . DLn, to define apixel array in an active region 122 of the board 12. A plurality ofsource driving controllers 18 are arranged on a periphery region of theboard 12 electrically connected to the flexible printed circuit boards16. The source driving controllers 18 are electrically connected to theflexible printed circuit boards 16 for receiving data signals to drivethe data lines DL1, DL2, . . . DLn. Similarly, a plurality of scanningdriving controllers 22 are arranged on another periphery region of theboard 12 for receiving control signals to drive the scanning lines GL1,GL2, . . . GLm.

The power supply of the printed circuit board 14 provides power voltages(for example, analog power voltages) to the source driving controllers18 and the scanning driving controllers 22 via conductive paths 19 and23, respectively. The conductive paths 19 and 23 are formed directly onthe surface of the board 12, those called as a mode of wiring on array(WOA). As shown in FIG. 1, the conductive path 19 provides the powervoltages to the source driving controllers 18 in a cascade frame, suchthat the power voltages are transmitted along a single direction.However, if the mode of wiring on array is used in the board 12 made ofglass, the resistance of the wires is high and a large change of thevoltage drop is produced. Therefore, the plurality of flexible printedcircuit boards 16 should be employed, for solving the problem inrelation to the differences of the input voltages (working voltages) ofthe source driving controllers 18 in the cascade frame. If the pluralityof flexible printed circuit boards 16 are employed, the conductive path19 will not be too long and the change of the voltage drop is decreased.

However, the manufacturing cost is high since employing the plurality offlexible printed circuit board. To decrease the manufacturing cost,there should have as few flexible printed circuit boards (for example,only one flexible printed circuit board) as possible. Furthermore, theinput voltages of the driving controllers should be substantially same.

What is needed is providing a driving circuit, which can solve the aboveproblems.

SUMMARY OF THE INVENTION

A driving circuit in accordance with an exemplary embodiment of thepresent invention is provided. The driving circuit includes a powersupply, a plurality of conductive paths and a plurality of drivingcontroller. The power supply provides a predetermined voltage. Theconductive paths are electrically connected to the power supply toreceive the predetermined voltage. Each driving controller iselectrically connected to one corresponding conductive path. The drivingcontrollers at least include a first driving controller and a seconddriving controller. The first driving controller has a first internalcircuit and a resistance adjustment unit. The first internal circuitemploys a first internal voltage to perform functions that should beprovided by the first driving controller. The resistance adjustment unitis electrically connected between a special conductive path of theconductive paths and the first internal circuit. The second drivingcontroller has a second internal circuit for employing a second internalvoltage to perform functions that should be provided by the seconddriving controller. A resistance value of the resistance adjustment unitis adjustable to make the first internal voltage same to the secondinternal voltage.

A driving controller capable of adjusting an internal impedance thereofin accordance with another exemplary embodiment of the present inventionis provided. The driving controller includes an internal circuit and aresistance adjustment unit. The internal circuit is configured foremploying an internal voltage to perform functions that should beprovided by the driving controller. The resistance adjustment unit iselectrically connected between a conductive path and the internalcircuit, and a resistance value of the resistance adjustment unit isadjustable to adjust the internal voltage by adjusting the resistancevalue of the resistance adjustment unit.

A driving circuit in accordance with other exemplary embodiment of thepresent invention is provided. The driving circuit includes a powersupply and a plurality of conductive paths and a plurality of drivingcontroller. The power supply provides a predetermined voltage. Theconductive paths are electrically connected to the power supply toreceive the predetermined voltage, and the conductive paths havedifferent resistance values. Each driving controller is electricallyconnected to a corresponding conductive path. The driving controllersreceive same voltages supplied from the conductive paths electricallyconnected to the driving controllers.

The present invention employs the special circuit designs, such as theinternal circuit and/or the external circuit designs of the drivingcontrollers, to compensate the working voltages (the internal voltage orthe input voltage) of the driving controllers. Therefore, even if asingle flexible printed circuit board is employed to provide the workingvoltages of the driving controllers, the working voltages of the drivingcontrollers are substantially same.

BRIEF DESCRIPTION OF THE DRAWINGS

The present invention will become more readily apparent to thoseordinarily skilled in the art after reviewing the following detaileddescription and accompanying drawings, in which:

FIG. 1 is a schematic block diagram of a conventional LCD panel.

FIG. 2 is a schematic block diagram of a driving circuit in accordancewith an exemplary embodiment of the present invention.

FIG. 3 is a schematic block diagram of a driving controller inaccordance with an exemplary embodiment of the present invention.

FIG. 4 is a schematic diagram of a resistance adjustment unit inaccordance with an exemplary embodiment of the present invention.

FIG. 5 is a schematic block diagram of a driving circuit in accordancewith another exemplary embodiment of the present invention.

FIG. 6 is a schematic diagram of a circuit for adjusting analog powerpotentials in accordance with another exemplary embodiment of thepresent invention.

FIG. 7 is a schematic diagram of a circuit for adjusting groundpotentials in accordance with another exemplary embodiment of thepresent invention.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

The present invention will now be described more specifically withreference to the following embodiments. It is to be noted that thefollowing descriptions of preferred embodiments of this invention arepresented herein for purpose of illustration and description only. It isnot intended to be exhaustive or to be limited to the precise formdisclosed.

Referring to FIG. 2, a driving circuit in accordance with a firstexemplary embodiment of the present invention is provided. In thisexemplary embodiment, the driving circuit 100 includes a power supply120, a flexible printed circuit board 140, a plurality of conductivepaths 150 and a plurality of driving controllers 160.

The power supply 120 is configured for providing a predeterminedvoltage. In this exemplary embodiment, the predetermined voltage is apotential difference between analog power terminals Xn_AVDD (n=1˜4) andground terminals Xn_GND (n=1˜4). The power supply 120 is also configuredfor providing a digital power potential DVDD. The power supply 120 iselectrically connected to the driving controllers 160 through theflexible printed circuit board 140 and the conductive paths 150.Concretely, analog power terminals (AVDD) and ground terminals (GND) ofthe driving controllers 160 are electrically connected to the analogpower terminals Xn_AVDD and the ground terminals Xn_GND via thecorresponding conductive paths 150, respectively. The drivingcontrollers 160 may be integrated circuits. Digital power terminals(DVDD) of the driving controllers 160 receive the digital powerpotential DVDD provided from the power supply 120 in a cascading mode.

Referring to FIG. 3, a driving controller in accordance with anexemplary embodiment of the present invention is provided. As shown inFIG. 3, each driving controller 160 includes an internal circuit 162, abonding area 163, a plurality of resistance adjustment units 164, aplurality of first adjustment pads Y0, Y1, Y2, . . . Yn, a plurality ofsecond adjustment pads S0, S1, S2, . . . Sn, and a plurality ofresistance adjustment circuits 166. The internal circuit 162 employs aninternal voltage (working voltage), which is a potential differencebetween an internal potential AVDD sent from the power terminal and aninternal potential GND sent from the ground terminal, to make thedriving controller 160 perform its functions. Various signals producedfrom the internal circuit 162 are sent out of the driving controller 160via the bonding area 163. Each resistance adjustment unit 164 iselectrically connected between a corresponding conductive path 150 andthe internal circuit 162, such that the driving controller 160 canemploy the resistance adjustment unit 164 to adjust the internalpotential AVDD and the internal potential GND. In this exemplaryembodiment, some first adjustment pads Y0, Y1 and Y2 are electricallyconnected to the ground terminal X1_GND of the power supply 120, andsome second adjustment pads S0, S1 and S2 are electrically connected tothe analog terminal X1_AVDD of the power supply 120. Other first andsecond adjustment pads not used are spare.

It should be noted that, in all first adjustment pads Y0, Y1, Y2 . . .Yn, which used to be electrically connected to the analog terminalX1_AVDD, are determined by the internal potential AVDD of the powerterminal of the internal circuit 162. There may be one or some firstadjustment pads electrically connected to the analog terminal X1_AVDD.Similarly, in all second adjustment pads S0, S1, S2 . . . Sn, which usedto be electrically connected to the ground terminal X1_GND, aredetermined by the internal potential GND of the ground terminal of theinternal circuit 162. One terminal of each resistance adjustment circuit166 is electrically connected to one corresponding first or secondadjustment pad Y0, Y1, Y2, . . . Yn or S0, S1, S2, . . . Sn. Anotherterminal thereof is electrically connected to the resistance adjustmentunit 164. In this exemplary embodiment, the resistance adjustmentcircuits 166 are simple conductive wires, and the amount thereof is sameto that of the first and second adjustment pads.

Referring to FIG. 4, the resistance adjustment unit in accordance withan exemplary embodiment of the present invention is provided. As shownin FIG. 4, the resistance adjustment unit 164 includes a firstresistance adjustment unit 164 a and a second resistance adjustment unit164 b. The first resistance adjustment unit 164 a is electricallyconnected to the adjustment pad AVDD to obtain a potential supplied fromthe analog power terminal X1_AVDD through the conductive path 150. Thefirst resistance adjustment unit 164 a includes a plurality oftransistors M1, a plurality of transistors M2 and a plurality ofresistors R. The adjacent transistors M1 are connected together inseries. Similarly, the adjacent transistors M2 are connected together inseries. The resistors R are electrically connected between thetransistors M1 and the corresponding transistors M2 respectively, suchthat the whole resistance value represented by the conductive path 150may be adjusted by turning on or off the transistors M1 and M2 to changecombination of the resistors R. Thus the internal potential AVDD may beadjusted correspondingly.

In this exemplary embodiment, the second resistance adjustment unit 164b is electrically connected to the adjustment pad GND to obtain apotential provided from the ground terminal X1_GND through theconductive path 150. The second resistance adjustment unit 164 bincludes a plurality of transistors M3, a plurality of transistors M4and a plurality of resistors R. The adjacent transistors M3 areconnected together in series. Similarly, the transistors M4 areconnected together in series. The resistors R are electrically connectedbetween the transistors M3 and the corresponding transistors M4respectively, such that the whole resistance value represented by theconductive path 150 may be adjusted by turning on or off the transistorsM3 and M4 to change combination of the resistors R. Thus the internalpotential GND may be adjusted correspondingly.

It should be noted that, in this exemplary embodiment, the transistorsM1 and M2 are p-type transistors and the transistors M3 and M4 aren-type transistors, however the present invention is not limited inthose. One skilled in the art could devise variations that are withinthe scope and spirit of the invention disclosed herein, includingselecting different elements and changing designs of the adjustmentcircuit. Furthermore, although the resistors R of this exemplaryembodiment are same, they also may be different under needs.

From the above, one terminal of each resistance adjustment circuit 166electrically connected to the resistance adjustment unit 164, is coupledto gate terminals of the corresponding transistors M1 and M2 or thetransistors M3 and M4, such that the resistance adjustment circuit 166can be used to transmit predetermined potentials, such as the potentialsprovided from the analog power terminal X1_AVDD or the ground terminalX1_GND, to control on/off states of the transistors electricallyconnected to this resistance adjustment circuit 166. Thus the drivingcontroller 160 is capable of internal impedance thereof.

It should be noted that, the resistance adjustment unit 164 of thedriving controller 160 is configured for adjusting the internalpotential AVDD and the internal potential GND of the internal circuit162 to adjust the internal voltage (the difference between the internalpotential AVDD and the internal potential GND) of the internal circuit162. Of course, the resistance adjustment unit 164 is designed to onlyadjust the internal potential AVDD or the internal potential GND toadjust the internal voltage. Furthermore, if only adjusting the internalpotential AVDD, the resistance adjustment unit 164 only includes thefirst resistance adjustment unit 164 a electrically connected to theanalog power terminal Xn_AVDD of the power supply 120, to adjust theinternal potential AVDD. Simultaneously, the ground terminal (an inputterminal for the internal potential GND) of the internal circuit 162 isconnected directly to the ground terminal Xn_GND of the power supply120. Similarly, if only adjusting the internal potential GND, theresistance adjustment unit 164 only includes the second resistanceadjustment unit 164 b electrically connected to the ground terminalXn_GND of the power supply 120, to adjust the ground potential GND.Simultaneously, the power terminal (an input terminal for the internalpotential AVDD) of the internal circuit 162 is connected directly to theanalog terminal Xn_AVDD of the power supply 120.

The present driving circuit 100 changes the internal impedances of thedriving controllers, such that the driving controllers 160 can have sameinternal potentials. The driving controllers 160 of the driving circuit100 may have same internal circuit frames. For example, each drivingcontroller 160 includes the internal circuit 162 and the resistanceadjustment unit 164 as shown in FIG. 3. Alternatively, the drivingcontrollers 160 of the driving circuit 100 may have difference internalcircuit frames. For example, some driving controllers, each includes theinternal circuit 162 and the resistance adjustment unit 164 as shown inFIG. 3, and some driving controllers, each only includes the internalcircuit 162 without the resistance adjustment unit 164. Of course, thepresent invention may include other variations. For example, somedriving controllers 160, each only includes the resistance adjustmentcircuit 164 a without the resistance adjustment circuit 164 b; somedriving controllers 160, each only includes the resistance adjustmentcircuit 164 b without the resistance adjustment circuit 164 a; and otherdriving controllers 160, each includes the resistance adjustment circuit164 a and the resistance adjustment circuit 164 b. In other words,variations may be employed if they can make the driving controllers ofthe driving circuit 100 have same internal voltages.

Referring to FIG. 5, a driving circuit in accordance with a secondexemplary embodiment of the present invention is provided. In thisexemplary embodiment, the driving circuit 200 includes a power supply220, a flexible printed circuit board 240, a conductive path 250 and aplurality of driving controllers 260. The present driving circuit 200compensates external impedance of the driving controllers to make thedriving controllers 260 have same potentials. The power supply 220 isconfigured for providing a predetermined voltage through the flexibleprinted circuit board 240. In this exemplary embodiment, thepredetermined voltage is the potential difference between an analogpower terminal AVDD and a ground terminal GND. The power supply is alsoconfigured for providing a digital power potential DVDD. The analogpower terminal AVDD and the ground terminal GND are configured formaking analog power terminals and ground terminals of the drivingcontrollers 260 have same potential differences (voltage) via theconductive path 250. In other words, the conductive path 250 is designedto make the analog power terminals X1_AVDD, X2_AVDD, X3_AVDD and X4_AVDDand the corresponding ground terminals X1_GND, X2_GND, X3_GND and X4_GNDproduce same potential differences therebetween.

Refer to FIGS. 5 and 6 together. FIG. 6 is a circuit diagram foradjusting the analog power terminals X1_AVDD, X2_AVDD, X3_AVDD andX4_AVDD of the driving controllers 260 as shown in FIG. 5 by a pluralityof conductive path 250. The conductive paths 250 are formed on the glassboard, and include a main conductive path 251 and a plurality ofaccessorial conductive paths 253. The main conductive path 251 iselectrically connected to the analog power terminal AVDD of the powersupply 220 to receive a predetermined analog power potential. For theaccessorial conductive paths 253, one terminal of each of theaccessorial conductive paths 253 is electrically connected to differentnodes of the main conductive path 251 respectively, and another terminalthereof is electrically connected to the analog power terminals X1_AVDD,X2_AVDD, X3_AVDD and X4_AVDD of the driving controllers 260 respectivelyas shown in FIG. 5.

In this exemplary embodiment, if resistance values between the adjacentnodes of the main conductive path 251 and a resistance value between afirst node adjacent to the power supply 220 and the power supply 220 areR, currents I passed through the accessorial conductive paths 253 aresame. In addition, an accessorial conductive path 253 (called as a firstaccessorial conductive path in following) adjacent to the power supply220 is electrically connected to a first node of the main conductivepath 251, and an accessorial conductive path (call as a secondaccessorial conductive path in following) far away from the power supply220 is electrically connected to a second node of the main conductivepath 251. If the first accessorial conductive path has a resistancevalue of R1, the second accessorial conductive path has a resistancevalue of R2, to achieve same potentials and same currents at the analogpower terminals X1_AVDD, X2_AVDD, X3_AVDD and X4_AVDD of the drivingcontrollers 260, R1 and R2 must satisfy a following equation:

$R_{2} = {R_{1} - {\frac{n*\left( {n - 1} \right)}{2}*R}}$

Wherein n is the amount of the nodes. Other accessorial conductive pathsare electrically connected to the main conductive path 251 to form n−2nodes between the first node and the second node. The resistance valuebetween the second node and the power supply 220 is n*R.

For example, as shown in FIG. 6, two (n=4) accessorial conductive paths253 are arranged between the first accessorial conductive path and thesecond accessorial conductive path, and the two accessorial conductivepaths 253 are electrically connected to the main conductive path 251respectively to form two nodes. The resistance value between the secondnode and the power supply 220 is 4R. R1 equals to 7R, and R2 equals toR. Furthermore, the two accessorial conductive paths arranged betweenthe first accessorial conductive path and the second accessorialconductive path, have resistance values of 4R and 2R respectively. Thatis, in this exemplary embodiment, the resistance values of theconductive paths are different to achieve same potentials at the analogpower terminals X1_AVDD, X2_AVDD, X3_AVDD and X4_AVDD of the drivingcontrollers 260 as shown in FIG. 5.

Refer to FIGS. 5 and 7. FIG. 7 is a circuit diagram for adjusting theground terminals X1_GND, X2_GND, X3_GND and X4_GND of the drivingcontrollers 260 as shown in FIG. 5 with same potentials by the pluralityof conductive paths 250. Similarly, the conductive paths 250 are formedon the glass board, and include a main conductive path and a pluralityof accessorial conductive paths. The main conductive path iselectrically connected to the ground terminal GND of the power supply220 to receive a predetermined ground potential. One terminals of theaccessorial conductive path are electrically connected to differentnodes of the main conductive path respectively; and another terminalsthereof are electrically connected to the ground terminals X1_GND,X2_GND, X3_GND and X4_GND of the driving controllers 260 as shown inFIG. 5.

The resistance values of the conductive paths 250 as shown in FIG. 7 aresame to those as shown in FIG. 6. The conductive paths 250 havedifferent resistance values such that the ground terminals X1_GND,X2_GND, X3_GND and X4_GND of the driving controllers 260 have samepotentials.

From FIGS. 6 and 7, since the analog power terminals X1_AVDD, X2_AVDD,X3_AVDD and X4_AVDD have the same potentials, the ground terminalsX1_GND, X2_GND, X3_GND and X4_GND also have the same potentials, theconductive paths 250 electrically connected to the driving controllers260 have the same voltages.

The driving circuit 200 of this exemplary embodiment, adjusts thepotentials of the power terminals and the ground terminals of thedriving controllers 260 such that the input voltages of the drivingcontrollers 260 are same. It should be noted that, this adjusting modemay be cooperated with the adjusting mode as shown in FIGS. 2 to 4.

From the above, those above embodiments of the present invention employthe special circuit designs, such as the internal circuit and/or theexternal circuit designs of the driving controllers, to compensate theworking voltages (the internal voltage or the input voltage) of thedriving controllers. Therefore, even if a single flexible printedcircuit board is employed to provide the working voltages of the drivingcontrollers, the working voltages of the driving controllers aresubstantially same.

Furthermore, the present driving circuits of the present invention maybe adapted in a TFT-LCD panel. The driving controllers of the drivingcircuit may be data driving controllers for driving data lines. It maybe understood that, the driving controllers of the driving circuit alsomay be scan driving controllers for driving scanning lines. Of course,the present driving circuits of the present invention may be not adaptedin the TFT-LCD panel, and may be adapted in other planar display panel.

While the invention has been described in terms of what is presentlyconsidered to be the most practical and preferred embodiments, it is tobe understood that the invention needs not be limited to the disclosedembodiment. On the contrary, it is intended to cover variousmodifications and similar arrangements included within the spirit andscope of the appended claims which are to be accorded with the broadestinterpretation so as to encompass all such modifications and similarstructures.

What is claimed is:
 1. A driving circuit, comprising: a power supply forproviding a predetermined voltage; a plurality of conductive pathselectrically connected to the power supply to receive the predeterminedvoltage, and the conductive paths having different resistance values;and a plurality of driving controllers, each of the driving controllersbeing electrically connected to one corresponding conductive path, andthe driving controllers receiving same voltages supplied from theconductive paths, wherein the conductive paths includes: a mainconductive path electrically connected to the power supply to receivethe predetermined voltage; and a plurality of accessorial conductivepaths, one terminals of the accessorial conductive paths beingelectrically connected to different nodes formed on the main conductivepath respectively, and another terminals thereof being electricallyconnected to the driving controllers respectively, wherein theaccessorial conductive paths comprises: a first accessorial conductivepath, one terminal thereof being electrically connected to a first nodeof the main conductive path, the first node being one of the nodes thatis most adjacent to the power supply, a resistance value between thefirst node and the power supply being R, a resistance value of the firstaccessorial conductive path being R1; and a second accessorialconductive path, one terminal thereof being electrically connected to asecond node formed on the main conductive path, the second node beingone of the nodes that is farthest away from the power supply, aresistance value between the second node and the power supply being n*R,a resistance value of the second accessorial conductive path being R2,wherein, other accessorial conductive paths are electrically connectedto the main conductive path to form n−2 nodes, which are between thefirst node and the second node, and currents passed through theaccessorial conductive paths are same, and R1 and R2 satisfy a followingequation: $R_{2} = {R_{1} - {\frac{n*\left( {n - 1} \right)}{2}*{R.}}}$2. The driving circuit as claimed in claim 1, wherein the plurality ofdriving controllers comprises: a first driving controller having a firstinternal circuit employing a first internal voltage to perform functionsprovided by the first driving controller, and a resistance adjustmentunit electrically connected between a special conductive path of theconductive paths and the first internal circuit; and a second drivingcontroller having a second internal circuit employing a second internalvoltage to perform functions provided by the second driving controller,wherein a resistance value of the resistance adjustment unit isadjustable to make the first internal voltage same to the secondinternal voltage.
 3. The driving circuit as claimed in claim 2, whereinthe resistance adjustment unit includes: a plurality of firsttransistors arranged in series; a plurality of second transistorsarranged in series; and a plurality of resistors electrically connectedbetween the first transistors and the second transistors respectively,to change a combination of the resistors such that the specialconductive path represents a different resistance value when turning ondifferent combinations of the first transistors and the secondtransistors.
 4. The driving circuit as claimed in claim 1, wherein eachof the plurality of driving controllers comprises: a internal circuitemploying a internal voltage to perform functions provided by thecorresponding driving controller; and a resistance adjustment unitelectrically connected between a special conductive path of theconductive paths and the internal circuit, wherein a resistance value ofthe resistance adjustment unit is adjustable to make the internalvoltage same to each of the plurality of driving controllers.
 5. Thedriving circuit as claimed in claim 4, wherein the resistance adjustmentunit includes: a plurality of first transistors arranged in series; aplurality of second transistors arranged in series; and a plurality ofresistors electrically connected between the first transistors and thesecond transistors respectively, to change a combination of theresistors such that the conductive path represents a differentresistance value when turning on different combinations of the firsttransistors and the second transistors.
 6. The driving circuit asclaimed in claim 5, further comprising: at least one resistanceadjustment circuit, one terminal thereof being electrically connected togate terminal of at least one of the first transistors and gate terminalof at least one of the second transistors, and another terminal of theresistance adjustment circuit being electrically connected to apredetermined potential, such that the resistance adjustment circuit isconfigured for transmitting the predetermined potential to controlon/off states of the at least one of the first transistors and the atleast one of the second transistors electrically connected to theresistance adjustment circuit.
 7. A driving circuit, comprising: a powersupply for providing a predetermined voltage; a plurality of conductivepaths electrically connected to the power supply to receive thepredetermined voltage, and the conductive paths having differentresistance values; and a plurality of driving controllers, each of thedriving controllers being electrically connected to one correspondingconductive path, and the driving controllers receiving same voltagessupplied from the conductive paths, wherein each of the plurality ofdriving controllers comprises: a internal circuit employing a internalvoltage to perform functions provided by the corresponding drivingcontroller; and a resistance adjustment unit electrically connectedbetween a special conductive path of the conductive paths and theinternal circuit, wherein a resistance value of the resistanceadjustment unit is adjustable to make the internal voltage same to eachof the plurality of driving controllers; wherein the resistanceadjustment unit includes: a plurality of first transistors arranged inseries; a plurality of second transistors arranged in series; and aplurality of resistors electrically connected between the firsttransistors and the second transistors respectively, to change acombination of the resistors such that the conductive path represents adifferent resistance value when turning on different combinations of thefirst transistors and the second transistors; wherein the drivingcircuit further comprises at least one resistance adjustment circuit,one terminal thereof being electrically connected to gate terminal of atleast one of the first transistors and gate terminal of at least one ofthe second transistors, and another terminal of the resistanceadjustment circuit being electrically connected to a predeterminedpotential, such that the resistance adjustment circuit is configured fortransmitting the predetermined potential to control on/off states of theat least one of the first transistors and the at least one of the secondtransistors electrically connected to the resistance adjustment circuit.